An implantable parametric circuit enables local signal amplification and wireless transmission of RF signals in connection with magnetic resonance imaging systems. The parametric circuit detects RF signal detected during magnetic resonance imaging procedure, amplifies the detected RF signal, and transmits the amplified RF signal in a wireless manner to an external pick-up coil. The parametric amplifier is also configured to use another RF signal generated by an external source as the primary power source. As a result, implanted or catheter coils could be used as a wireless signal transducer without the need for a battery or a power connection.